Battery charger



FIG. 1 is a front elevational view of a battery charger showing my new design;

FIG. 2 is a rear elevational view of the battery charger;

FIG. 3 is a right side elevational view of the battery charger;

FIG. 4 is a left side elevational view of the battery charger;

FIG. 5 is a top plan view of the battery charger; and,

FIG. 6 is a bottom plan view of the battery charger. 

The ornamental design for a battery charger, as shown and described. 